operator issues

Problem

The exact same code might behave different when executed from the script editor compared to when executed after pressing a QT button.

Blender Operators often fail when run from QT, because they rely on the active window & other context properties. But when running a QT tool, the active window is None, leading to an error.

This sample code works in Blender, but won't work if run from qt.

import bpy
bpy.ops.mesh.primitive_cube_add(location=(0.0, 0.0, 0.0))  # this works
bpy.ops.object.modifier_add(type='SOLIDIFY')  # missing active object in context error

Fix

context override

bqt utils

bqt ships with a decorator you can add to your functions, like this:

import bqt.utils

@bqt.utils.context_window
def my_method():
    do operator magic

This will fix the majority of issues, but not all of them. You can also do the exact same manually, with a context override.

manual context override

To work around this, you can override the context.

e.g. this is what happens under the hood of the above decorator

window = bpy.context.window_manager.windows[0]
with bpy.context.temp_override(window=window):
    original_code ...

to override additional context properties, just add them to the temp_override:

with bpy.context.temp_override(window=window, object=obj, active_object=obj):